Mechanical joint for vacuum-tubes.



D. MCF. MOORE. MECHANICAL JOINT FCR VACUUM TUBES. APPLIUATIQN FILED A211. 16, 1908.

995,025. Patented Julie 13,1911.

ITED STATES PATENT OFFICE.

DANIEL MCFARLAN MOORE, OF NEWARK, NEW JERSEY, ASSIGNOR TO MOORE ELEC- TRICAL'COMPANY, OF NEW YORK, N. Y., A CORPORATION 0F NEW YORK.

MECHANICAL JOINT FOR VACUUM-TUBES'.

specification pf Letters Patent. Patented June 13, 1911 f Application filed April 16, 1908. Serial No. 427,367.

To all whom it may concern: f

Be it known that I, DANIEL McFnRLAN MooRE, a citizen of the United States, and a resident` of Newark, in the county of Essex and State of New Jersey, have invented cer tain new and useful Improvements in Mechanical Joints for Vacuum-Tubes., of which the following is a specification, j

My invention relates to gas-tight joints or seals for vacuum tubes, and is designed, primarily, to avoid certain difficulties incident to the use of a material that will readily fuse, melt or disintegrate under the action of heat, although the invention is likewise useful for joints of vacuum tubes which are liable to damage by expansion and contraction arising from the heating effect of the electric discharge passing through the tube, and the subsequent contraction of the joint when the discharge ceases. l

Another part of my invention' consists of an improvement in the mechanical structure of the .joint and has for its object to provide a joint of very simple construction and with a minimum of parts. c

Briefly stated, my invention consists in providingthe tube at the joints with means for contracting the electricdischarge so as to direct it away from the joint at the wall` of the tube and thereby prevent, as far as ossible, the heatingof the joint with the damaging or deteriorating effects above mentioned. i

My invention consists furtherv in the special constructions or forms given to the tube ends at the joint and tothe special construction of joint itself, as hereinafter more particularly described and then specified in the claims.

f In the accompanying drawings, Figure 1.

is a longitudinal section through the end portions of two tube sections at the joint and shows one of the constructions embody-4 ing my invention.

as at 4, so as to produce a contraction in the bore or passage through which the electric discharge passes.- The general path of the discharge through this contraction, so that said discharge will be directed away from the junction of the tube section, is indicated .by the dotted line and, as shown, passes through' the contracted mouth of one of the tube sections. The end or mouth of the other tubesection is expanded or out-turned aas indicated at 5, and said out-turned por-l tion or mouth receives the inturned end of the opposite tube section, theA two parts be-v ing fitted, if desired, as aground joint. If desired, a plastic sealing material or cement as indicated bythe heavy black lines may 'be' used between the abutting surfaces or `said sealed joint may be formedfin any other desired way, and-by the use of any other desired materials. As will be seen, the electric discharge being obliged to pass through the contracted mouth or end of the tube, is directed away from the joint, so that the latter will not become heated to nearly as great an extent as it would if the discharge were permitted to pass through the tube at the joint without anly contraction of bore of the completed tu e.

Instead of forming a contraction in the tube itself, a separate connecting tube 7 may be located at the joint, as shown in Fig. 2, said tube practically filling `thebore of the tube sections at its ends, but being contracted between its vends under the main`portion of the joint so as to contract the discharge and thereby lessening the heating of the joint by such discharge.4 In this figure, a vmodification of the joint itself isshown. 8 isla sleeve of thin metal or other suitable material encircling and fitting closely upon ythe meeting ends of the .tube sections and spanning the line between them. A binding wire, cord or tape of metal or `other material, indicated at 9, binds the said sleeve;l closely upon the tubes and over all is 'applied a mass of some cementing or Sealing material .10, preferably one which will harden and which will thereby anchor the tubes and the other portions of the sealing joints. For this sealing material or cement, I use sealing wax, but have employed other materials or substances and as will be evident to those skilled in the art many other materials would j be suitable for the purpose. 1

What I claim as my invention is 1. An electrically operated vacuum tube built up in sections joined to ether having a contraction for the electric discharge at its joints.y

2. An electrically operated vacuum tube made yup in sections sealed at the joint by- Ithe aid of a material liable to fusion or dis- '3. A11 electrically operated' vacuum tube built u p in sections joined together end to l .Y end adapted to contract' the electric disj 10 charge.

end,'one of the sections having an inturned 4. A section'of vaciium tube having an exj anded andinturned end adapted to prof v uce a contraction inthe bore of the tubing combined withv anv adjacent section having j, j

`'2' Y j l995,025

an lexpanded or out-turned end, as and for 15 v,the 'purpose described'.

5. lectric vacuum tube made in sections joined together and means for contractingthe electric discharge at the joints between sections. 20

Signed at New York in the county ofNew York and State of New York this lfth day of April A. D. 1908. o

DANIEL'MCFAARLAN MOORE. Witnesses: I

C. F. TrscHNER, J LILUAN BLoND. A 

